| 摘要 |
PURPOSE:To obtain a lightweight, high elastic and high internal-loss acoustic vibrator by forming the vibrator by using a kneaded material which consists essentially of polypropylene and flake graphite powder and by orienting the flake graphite powder along the surface. CONSTITUTION:With a single component of polypropylene or a mixture of polypropylene and polymethylmethacrylate, a rubbery material, such as acrylonitrile butadiene rubber, isobutylene-isoprene rubber and styrene-butadiene rubber, is mixed as required to obtain mixed material 1. Then, a mixture of said mixed material 1 and flake graphite powder 2 is molded into acoustic vibrator A. In this cas, graphite powder 2 is oriented along the surface. |
